1. Field of the Invention
This invention relates generally to a model racing car, and more specifically to a model racing car of the front drive type that is adapted to control the steering angle of front wheels by the output of a radio control receiver wherein the left and right front wheels are independently driven by drive motors mounted on each of the front wheels through the use of reduction gear devices, and each driving block integrally constructed of the front wheels, the reduction gear device and the drive motor is controlled by the output of the radio control receiver.
2. Description of the Prior Art
In most conventional model racing cars, the so-called rear-drive, front-control system in which driving force is applied to the rear wheels and the control of the travelling direction is effected by the front wheels has usually been adopted. In a model racing car of this type, however, unwanted phenomena such as the slipping of wheels during turning or spin turns due to the slip tend to occur when it travels on a flat floor surface, particularly at high travelling speed. To prevent such phenomena, the so-called front-drive system in which both the driving direction control and the application of driving force are effected on front wheels has been devised.
In a model racing car of the front drive type, as shown in FIG. 1, left and right front wheels 1 are driven by a drive shaft 4 with a differential gear device 3 driven by a drive motor 2 through the use of a universal joint 5, and the steering angle of the front wheels 1 is controlled by a tie rod 6 controlled in the direction shown by an arrow in the FIGURE by the output of a radio control receiver (not shown). As described above, a model racing car of the conventional front-drive type has the following disadvantages in terms of the construction of drive assembly.
(1) The differential gear device 3 of a complicated mechanism is required.
(2) The use of the universal joint 5 to couple the drive shaft 4 and the front wheels 1 may cause problems in terms of the strength and wear of the universal joint 5. In addition, the limited bending angle of the universal joint 5 restricts the control range of the steering angle of the front wheels 1.
(3) The construction of the linkage (not shown) between the tie rod 6 for controlling the steering angle of the front wheels and the axle shafts of the front wheels becomes complicated.
(4) Since the construction of the drive assembly involves the use of the differential gear device 3 and the universal joint 5, a multiple number of bearings (not shown) are required on the axle shafts of the front wheels 1 and the drive shaft 4. This results in a complicated mechanism and problems such as the wear of the bearings and poor assembling accuracy.